CN109320403A - A kind of preparation method of 2,5- dibromophenol - Google Patents
A kind of preparation method of 2,5- dibromophenol Download PDFInfo
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- CN109320403A CN109320403A CN201811421573.6A CN201811421573A CN109320403A CN 109320403 A CN109320403 A CN 109320403A CN 201811421573 A CN201811421573 A CN 201811421573A CN 109320403 A CN109320403 A CN 109320403A
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- reaction
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- diazotising
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C201/00—Preparation of esters of nitric or nitrous acid or of compounds containing nitro or nitroso groups bound to a carbon skeleton
- C07C201/06—Preparation of nitro compounds
- C07C201/12—Preparation of nitro compounds by reactions not involving the formation of nitro groups
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C213/00—Preparation of compounds containing amino and hydroxy, amino and etherified hydroxy or amino and esterified hydroxy groups bound to the same carbon skeleton
- C07C213/02—Preparation of compounds containing amino and hydroxy, amino and etherified hydroxy or amino and esterified hydroxy groups bound to the same carbon skeleton by reactions involving the formation of amino groups from compounds containing hydroxy groups or etherified or esterified hydroxy groups
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C37/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring
- C07C37/01—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring by replacing functional groups bound to a six-membered aromatic ring by hydroxy groups, e.g. by hydrolysis
- C07C37/055—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring by replacing functional groups bound to a six-membered aromatic ring by hydroxy groups, e.g. by hydrolysis the substituted group being bound to oxygen, e.g. ether group
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C41/00—Preparation of ethers; Preparation of compounds having groups, groups or groups
- C07C41/01—Preparation of ethers
- C07C41/18—Preparation of ethers by reactions not forming ether-oxygen bonds
- C07C41/22—Preparation of ethers by reactions not forming ether-oxygen bonds by introduction of halogens; by substitution of halogen atoms by other halogen atoms
Abstract
The invention discloses a kind of industrialized process for preparing of 2,5- dibromophenol.The industrialized process for preparing of 2, the 5- dibromophenol, using 2- amino -5- Nitroanisole as initial feed, through bromine in diazonium, reduction, bromine and demethylation four-step reaction synthesize 2,5- dibromophenol in diazotising again.2, the 5- dibromophenol that this process obtains is black solid, and purity 97.5%, every step feed stock conversion respectively reaches 100%, and the total recovery of whole process reaches 34%.
Description
Technical field
The present invention relates to a kind of production methods of medicine intermediate, specifically, the present invention is one kind 2,5- dibromophenol
Preparation method.
Background technique
2,5- dibromophenol is mainly used for pharmaceuticals industry and material at present.Such as can be used for: 1) synthesis has spiral chirality knot
The alkynyl ring flower astragalus class compound of structure, this kind of compound are potential new liquid crystal structure chemical combination objects 2) synthesize fragrant sulfo group pyrroles
Pyridine compounds and their, for treating 5-HT6 receptor adjustment class disease 3) two phenoxy group class compounds are synthesized as intracellular calcareous
Regulator.
Currently, there are two types of method, Kulamani(PCT 2016055028 for the synthesis report of target compound) describe one
Kind is seemed simply with the method that phenol is that the direct bromo of raw material prepares object, this method, and product is very miscellaneous in fact, is separated non-
It is often difficult, substantially without practical value.Another synthetic method report is more, and usual starting material is paradibromobenzene, nitration mixture
It nitrifying, Reduction with Stannous Chloride, phenolic hydroxyl group in diazonium, three step yields are respectively 68%, 97% and 41% or so, although yield is higher,
But mixed acid nitrification, the high requirements on the equipment, Reduction with Stannous Chloride post-process more complicated (PCT 2010024980).Therefore, it opens
The synthetic route for sending out a suitable industrialized production is very necessary.
Summary of the invention
The object of the present invention is to provide methods and technique that one synthesizes 2,5- dibromophenol, to meet industrial production need
It wants.
The method of the present invention is as raw material, through overprotection, nitrification, deprotection, bromo, to take off 2- amino -5- Nitroanisole
Five step of amino reaction synthesis 2,5- dibromophenol, this method includes following reaction equation:
The preparation method of the present invention 2,5- dibromophenol carries out as steps described below:
(1) bromine reaction in diazotising: 2- amino -5- Nitroanisole is added into reaction vessel, adds 30% or so sulphur
Then sodium nitrite solution is added dropwise in acid, stirring, dropwise addition process control temp is at 0~25 DEG C, preferable temperature range 5~15
DEG C, ratio range 2.5:1.1:1.0~10.5 of sulfuric acid and the amount of sodium nitrite and the substance of 2- amino -5- Nitroanisole:
1.5:1.0 preferable ratio range is 5.0:1.3:1.0.It adds, stirring a period of time, it is spare to be prepared into diazonium salt.
Cuprous bromide and HBr, cuprous bromide used and 2- amino -5- nitrobenzoyl are added in another reaction flask
The ratio range of the amount of the substance of ether is 0.25~0.75:1, and preferable ratio range is 0.5~0.6:1.Hydrobromic acid and 2- amino-
The ratio of the amount of the substance of 5- Nitroanisole is 1.1~3:1, and preferable ratio is 1.1~1.3:1.It is added under stirring condition
Above-mentioned diazonium salt, when decomposition, 35~90 DEG C of reaction temperature control range, 40~65 DEG C of preferred range.It finishes, continues to stir
It mixes, insulation reaction for a period of time, stirs, and it is cooling, it filters, obtains the bromo- 5- Nitroanisole of brown-red solid 2-.
(2) reduction reaction: being added iron powder, water in the reactor, stirs, then heating is added portionwise step nitro compounds, adds
Expect process temperature control at 70~105 DEG C, 85~100 DEG C of preferred range, 90~95 DEG C of optimum temperature range.
The ratio range of the amount of the substance of iron powder and the bromo- 5- Nitroanisole of 2- used is 4.0~10.5:1, is preferably compared
Value range is 4.0~4.5:1.It finishes, GC tracking, until fully reacting.After the reaction was completed, cooling, it is after the reaction was completed, cooling,
Ethyl acetate is added, filters, mother liquor separates oil reservoir, rotates, obtains the bromo- 5- aminoanisole of brownish black solid 2-.
(3) bromine reaction in diazonium again: the bromo- 5- aminoanisole of 2- is added into reaction vessel, adds 30% or so sulphur
Then sodium nitrite solution is added dropwise in acid, stirring, dropwise addition process control temp is at 0~25 DEG C, preferable temperature range 5~15
DEG C, ratio range 2.5:1.1:1.0~10.5 of sulfuric acid and the amount of sodium nitrite and the substance of 2- amino -5- Nitroanisole:
1.5:1.0 preferable ratio range is 5.0:1.3:1.0.It adds, stirring a period of time, it is spare to be prepared into diazonium salt.
Cuprous bromide and HBr, cuprous bromide used and the bromo- 5- aminoanisole of 2- are added in another reaction flask
Substance amount ratio range be 0.25~0.75:1, preferable ratio range be 0.5~0.6:1.Hydrobromic acid and the bromo- 5- ammonia of 2-
The ratio of the amount of the substance of base methyl phenyl ethers anisole is 1.1~3:1, and preferable ratio is 1.1~1.3:1.It is added under stirring condition above-mentioned
Diazonium salt, when decomposition, 35~90 DEG C of reaction temperature control range, 40~65 DEG C of preferred range.It finishes, continues to stir,
Insulation reaction for a period of time, stirs, cooling, filters, obtains brown solid 2,5- dibromo methyl phenyl ethers anisole.
(4) product 2,5- dibromo methyl phenyl ethers anisole, the DMF of third step demethylating reaction: are added into reaction vessel.Solvent DMF
The ratio range of volume and 2,5- dibromo methyl phenyl ethers anisole quality is 3~15:1, and preferable ratio range is 4~6:1.Reaction temperature control
30~120 DEG C of range, 80~100 DEG C of preferable temperature controlling range.Be added portionwise alchlor under stirring, alchlor with
Ratio range with the amount of 2,5- dibromo methyl phenyl ethers anisole substance is 1~5:1, and preferable ratio range is 1.1~1.3:1.GC tracking, directly
Terminate to reaction.After the reaction was completed, dichloroethanes and water, liquid separation is added.It is oily mutually to wash, then liquid separation, obtained oily phase precipitation.?
To black solid 2,5- dibromophenol.
Specific embodiment 1
(1) bromine reaction in diazotising: 200 g of 2- amino -5- Nitroanisole is added into reaction vessel, adds 30% or so
1950 g of sulfuric acid, then stirring is added dropwise the solution being made by 107 g sodium nitrites and 300 mL water, process control temperature is added dropwise
Degree is at 8 DEG C or so.It adds, stirring a period of time, it is spare to be prepared into diazonium salt.
110 g of cuprous bromide and 300 g HBr is added in another reaction flask, above-mentioned diazonium is added under stirring condition
Salt, temperature can rise when decomposition, and process temperature control is added dropwise at 40~65 DEG C.It finishes, continues to stir, at one section of insulation reaction
Between, it stirs, it is cooling, it filters, washes, it is dry, obtain bromo- 262 g of 5- Nitroanisole of brown-red solid 2-, 97% or more content,
Yield 95%.
(2) reduction reaction: being added 220 g of iron powder, water in the reactor, stirs, then step nitro is added portionwise in heating
260 g of object, charging process temperature control is at 90~95 DEG C.It finishes, GC tracking, until fully reacting.It is after the reaction was completed, slightly cold,
Ethyl acetate extraction is added, filters, liquid separation, revolving obtains bromo- 178 g of 5- aminoanisole of brownish black solid 2-, content 98%,
Yield 78%.
(3) bromine reaction in diazonium again: bromo- 170 g of 5- aminoanisole of 2- is added into reaction vessel, adds 30% or so
1380 g of sulfuric acid, then stirring is added dropwise the solution liquid being made by 75 g sodium nitrites and 200 g water, process control temperature is added dropwise
Degree is at 12 DEG C or so.It adds, stirring a period of time, it is spare to be prepared into diazonium salt.
Cuprous bromide 220 g of 90 g and HBr is added in another reaction flask, above-mentioned diazonium is added under stirring condition
Salt, when decomposition, temperature can be increased, and control temperature at 40~65 DEG C.It finishing, continues to stir, insulation reaction for a period of time, stirs,
It is cooling, it filters, obtains brown solid 2,174 g of 5- dibromo methyl phenyl ethers anisole, content is greater than 97%, yield 78%.
(4) 170 g, DMF 900 of product 2,5- dibromo methyl phenyl ethers anisole of third step demethylating reaction: is added into reaction vessel
mL.102 g of alchlor is added portionwise in stirring, control temperature at 80~100 DEG C.GC tracking, until reaction terminates.Reaction
After the completion, dichloroethanes and water, liquid separation is added.Oily mutually washing, then liquid separation, obtained oily phase precipitation obtain black solid 2,5-
82 g of dibromophenol, content 98%, yield 50.7%.
Specific embodiment 2
(1) bromine reaction in diazotising: 1200 g of 2- amino -5- nitrobenzoyl is added into reaction vessel, adds 30% or so
Then the solution being made by 660 g sodium nitrites and 1500 mL water is added dropwise in 12000 g of sulfuric acid, stirring, process control temperature is added dropwise
Degree is at 8 DEG C or so.It adds, stirring a period of time, it is spare to be prepared into diazonium salt.
670 g of cuprous bromide and 1850 g HBr is added in another reaction flask, is added under stirring condition above-mentioned heavy
Nitrogen salt, temperature can rise when decomposition, and process temperature control is added dropwise at 40~65 DEG C.It finishes, continues to stir, one section of insulation reaction
Time stirs, cooling, filters, and washes, dry, obtains bromo- 1608 g of 5- Nitroanisole of brown-red solid 2-, content 97% with
On, yield 97%.
(2) reduction reaction: being added 1330 g of iron powder, water in the reactor, stirs, then step nitre is added portionwise in heating
1560 g of substratess, charging process temperature control is at 90~95 DEG C.It finishes, GC tracking, until fully reacting.After the reaction was completed, slightly
It is cold, ethyl acetate extraction is added, filters, liquid separation, revolving obtains bromo- 1125 g of 5- aminoanisole of brownish black solid 2-, content
98%, yield 82%.
(3) bromine reaction in diazonium again: bromo- 1020 g of 5- aminoanisole of 2- is added into reaction vessel, adds 30% or so
8380 g of sulfuric acid, then stirring is added dropwise the solution liquid that 455 g sodium nitrites and 1000 g water are made into, process control temperature is added dropwise
Degree is at 12 DEG C or so.It adds, stirring a period of time, it is spare to be prepared into diazonium salt.
520 g and HBr1350 g of cuprous bromide is added in another reaction flask, above-mentioned diazonium is added under stirring condition
Salt, when decomposition, temperature can be increased, and control temperature at 40~65 DEG C.It finishing, continues to stir, insulation reaction for a period of time, stirs,
It is cooling, it filters, obtains brown solid 2,1086 g of 5- dibromo methyl phenyl ethers anisole, content is greater than 97%, yield 81%.
(4) product 2,5- dibromo methyl phenyl ethers anisole 1080 g, DMF of third step demethylating reaction: are added into reaction vessel
5500 mL.688 g of alchlor is added portionwise in stirring, control temperature at 80~100 DEG C.GC tracking, until reaction terminates.
After the reaction was completed, dichloroethanes and water, liquid separation is added.Oily mutually washing, then liquid separation, obtained oily phase precipitation obtain black solid
2,5- dibromophenol 548g, content 98%, yield 53.3%.
Claims (7)
- The preparation method of 1.2,5- dibromophenols, it is characterized in that using 2- amino -5- Nitroanisole as raw material, through bromine in diazonium, Reduction, bromine and demethylation four-step reaction synthesize 2,5- dibromophenol in diazotising again.
- 2. the preparation method of 2,5- dibromophenol as described in claim 1, it is characterised in that in diazotising when bromine reaction, diazonium Change reagent selection strong acid (hydrochloric acid or sulfuric acid) and nitrous acid, preferably sulfuric acid and sodium nitrite are as diazo reagent；In diazotising When bromine reaction is at salt, the ratio range 2.5 of the amount of the substance of sulfuric acid used, sodium nitrite and 2- amino -5- Nitroanisole: 1.1:1.0~10.5:1.5:1.0, preferable ratio range are 5.0:1.3:1.0；When bromine reaction is at salt in diazotising, reaction temperature 0~25 DEG C of control range, 5~15 DEG C of preferred range.
- 3. the preparation method of 2,5- dibromophenol as described in claim 1, it is characterised in that when bromine reaction decomposes in diazotising, Catalyst choice cuprous salt or copper powder, preferably cuprous bromide is as catalyst；When bromine reaction decomposes in diazotising, bromination used The cuprous mass values range with diazonium salt is 0.25~0.75:1, and preferable ratio range is 0.5~0.6:1；Bromine in diazotising When reaction is decomposed, preferably hydrobromic acid is brominated reagent；Hydrobromic acid and the ratio of the amount of the substance of 2- amino -5- Nitroanisole are 1.1~3:1, preferable ratio are 1.1~1.3:1；When bromine reaction decomposes in diazotising, reaction temperature control range 35~90 DEG C 40~65 DEG C of preferred range.
- 4. the preparation method of 2,5- dibromophenol as described in claim 1, it is characterised in that when nitro-reduction reaction, reducing agent Iron powder or hydrazine hydrate are selected, preferably iron powder is as reducing agent；When nitro-reduction reaction, iron powder used and the bromo- 5- nitrobenzene of 2- The ratio range of the amount of the substance of methyl ether is 4.0~10.5:1, and preferable ratio range is 4.0~4.5:1；Nitro-reduction reaction When, 70~105 DEG C of reaction temperature control range, 85~100 DEG C of preferred range, 90~95 DEG C of optimum temperature range.
- 5. the preparation method of 2,5- dibromophenol as described in claim 1, it is characterised in that again in diazotising bromine reaction at When salt, diazo reagent selects strong acid (hydrochloric acid or sulfuric acid) and nitrous acid, when bromine reaction is at salt in diazotising again, preferably sulfuric acid With sodium nitrite as diazo reagent；When bromine reaction is at salt in diazotising again, sulfuric acid, sodium nitrite and the bromo- 5- of 2- used Ratio range 3.5:1.1:1.0~10.5:1.5:1.0 of the amount of the substance of aminoanisole, preferable ratio range are 3.0: 1.4:1.0；When bromine reaction is at salt in diazotising again, 10~40 DEG C of reaction temperature control range, preferred range 15~25 ℃。
- 6. the preparation method of 2,5- dibromophenol as described in claim 1, it is characterised in that bromine reaction point in diazotising again Xie Shi, catalyst choice cuprous salt or copper powder, preferably cuprous bromide is as catalyst；When bromine reaction decomposes in diazotising again, Cuprous bromide used and mass values range be 0.25~0.75:1, preferable ratio range is 0.5~0.6:1；It weighs again When bromine reaction decomposes in nitridation, preferably hydrobromic acid is brominated reagent, hydrobromic acid and the amount of the substance of the bromo- 5- aminoanisole of 2- Ratio is 1.1~3:1, and preferable ratio is 1.1~1.3:1；When bromine reaction decomposes in diazotising again, reaction temperature controls model Enclose 35~75 DEG C, 50~65 DEG C of preferred range.
- 7. the preparation method of 2,5- dibromophenol as described in claim 1, it is characterised in that when demethylation, solvent used is DMF, DMSO etc., wherein being excellent with DMF；When demethylation, the ratio range of solvent DMF volume and 2,5- dibromo methyl phenyl ethers anisole quality is 3~15:1, preferable ratio range are 4~6:1；When demethylation, using alchlor as demethylation reagent, alchlor with 2,5- The ratio range of the amount of dibromo methyl phenyl ethers anisole substance is 1~5:1, and preferable ratio range is 1.1~1.3:1；When demethylation, reaction temperature Degree is 30~120 DEG C, and preferred temperature range is 80~100 DEG C.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN109970513A (en) * | 2019-03-04 | 2019-07-05 | 宝鸡文理学院 | A method of phenol in catalysis recycling methanol method synthesis methyl phenyl ethers anisole technique |
| CN114560771A (en) * | 2022-03-07 | 2022-05-31 | 中北大学 | Method for selective nitration of bromophenol by photocatalysis |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN109970513A (en) * | 2019-03-04 | 2019-07-05 | 宝鸡文理学院 | A method of phenol in catalysis recycling methanol method synthesis methyl phenyl ethers anisole technique |
| CN109970513B (en) * | 2019-03-04 | 2021-12-28 | 宝鸡文理学院 | Method for catalytically recovering phenol in anisole synthesis process by methanol method |
| CN114560771A (en) * | 2022-03-07 | 2022-05-31 | 中北大学 | Method for selective nitration of bromophenol by photocatalysis |
| CN114560771B (en) * | 2022-03-07 | 2023-10-27 | 中北大学 | Method for photocatalytic selective nitration of bromophenol |
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Application publication date: 20190212 |